Extraordinary magneto-optical effect of a change in the phase of diffraction orders in dielectric diffraction gratings

Abstract

A phase magneto-optical effect in periodic diffraction structures, i.e., a resonant change in the phase of the diffraction order under a change in the magnetization of the material of a structure, has been considered. The theoretical description of the effect is given in terms of the resonant excitation of an eigen-mode of the periodic structure and the magnetization dependence of the frequency of the mode. It has been shown that a wide range of variation of the phase of the zeroth diffraction order is reached at a certain relation between the resonance and nonresonance diffraction processes. The magneto-optical effects in a dielectric diffraction grating formed by a periodic system of slits on a homogeneous substrate have been numerically simulated. The grating is magnetized in the plane and the magnetization vector is perpendicular to the slits of the grating. According to the numerical simulation, the phase magneto-optical effect in the zeroth diffraction order is two orders of magnitude larger than a similar effect for a homogeneous magnetic layer. The numerical simulation of phase magneto-optical effects confirms the theoretical description of the magneto-optical effect.